The present invention relates to the human interleukin-11 receptor, fragments thereof and recombinant polynucleotides and cells useful for expressing such proteins.
A variety of regulatory molecules, known as cytokines, have been identified including interleukin-11 (IL-11). The various protein forms of IL-11 and DNA encoding various forms of IL-11 activity are described in Bennett, et al., U.S. Pat. No. 5,215,895 (Jun. 1, 1993); McCoy, et al, U.S. Pat. No. 5,270,181 (Dec. 14, 1993); and McCoy, et al., U.S. Pat. No. 5,292,646 (Mar. 8, 1994), all incorporated herein by reference. Thus, the term xe2x80x9cIL-11xe2x80x9d includes proteins having the biological activity described in these patents, whether produced by recombinant genetic engineering techniques; purified from cell sources producing the factor naturally or upon induction with other factors; or synthesized by chemical techniques; or a combination of the foregoing.
IL-11 is a pleiotropic cytokine that has been implicated in production of several biological activities including: induction of multipotential hematopoietic progenitor cell proliferation (Musashi et al. (1991) Blood, 78, 1448-1451); enhancement of megakaryocyte and platelet formation (Burstein et al. (1992) J. Cell. Physiol., 153, 305-312); stimulation of acute phase protein synthesis (Baumann et al. (1991) J. Biol. Chem., 266, 20424-20427); inhibition of adipocyte lipoprotein lipase activity (Kawashima et al. (1991) FEBS Lett., 283, 199-202); and effects on neurotransmitter phenotype (Fann et al. (1994) Proc. Natl. Acad. Sci. USA, 91, 43-47).
IL-11 may be used in a pharmaceutical preparation or formulation to treat immune deficiencies, specifically deficiencies in hematopoietic progenitor cells, or disorders relating thereto. Treatment of the other disorders or stimulation of the immune systems of cells thereof may also employ IL-11. IL-11 may also be employed in methods for treating cancer and other disease. Such pathological states may result from disease, exposure to radiation or drugs, and include, for example, leukopenia, bacterial and viral infections, anemia, B cell or T cell deficiencies such as immune cell or hematopoietic cell deficiency following a bone marrow transplantation. IL-11 may also be used to potentiate the immune response to a variety of vaccines creating longer lasting and more effective immunity. Therapeutic treatment of cancer and other diseases with IL-11 may avoid undesirable side effects caused by treatment with presently available drugs.
Like most cytokines, IL-11 exhibits certain biological activities by interacting with an IL-11 receptor (IL-11R) on the surface of target cells. It would be desirable to identify and clone the sequence for the human receptor so that IL-11R proteins can be produced for various reasons, including production of therapeutics and screening for inhibitors of IL-11 binding to the receptor and receptor signalling.
In accordance with the present invention, polynucleotides encoding the human interleukin-11 receptor are disclosed. In certain embodiments, the invention provides an isolated polynucleotide comprising a nucleotide sequence selected from the group consisting of:
(a) the nucleotide sequence of SEQ ID NO:1 from nucleotide 803 to nucleotide 1999;
(b) a nucleotide sequence varying from the sequence of the nucleotide sequence specified in (a) as a result of degeneracy of the genetic code;
(c) an allelic variant of the nucleotide sequence specified in (a); and
(d) a fragment of (a) or (b) encoding a protein having the ability to bind IL-11.
Preferably, the nucleotide sequence encodes a protein having a biological activity of the human IL-11 receptor. The nucleotide sequence may be operably linked to an expression control sequence. In preferred embodiments, the polynucleotide comprises the nucleotide sequence of SEQ ID NO:1 from nucleotide 803 to nucleotide 1999 or a fragment thereof; the nucleotide sequence of SEQ ID NO:1 from nucleotide 803 to nucleotide 1828 or a fragment thereof; the nucleotide sequence of SEQ ID NO:1 from nucleotide 1904 to nucleotide 1999 or a fragment thereof; the nucleotide sequence of SEQ ID NO:1 from nucleotide 734 to nucleotide 1999 or a fragment thereof; the nucleotide sequence of SEQ ID NO:1 from nucleotide 1067 to nucleotide 1828 or a fragment thereof; or the nucleotide sequence of SEQ ID NO:1 from nucleotide 1067 to nucleotide 1999 or a fragment thereof. Other preferred embodments include the nucleotide sequence of SEQ ID NO:1 from nucleotide 734 to nucleotide 1828; the nucleotide sequence of SEQ ID NO:1 from nucleotide 734 to nucleotide 1810; the nucleotide sequence of SEQ ID NO:1 from nucleotide 734 to nucleotide 1768; and the nucleotide sequence of SEQ ID NO:1 from nucleotide 734 to nucleotide 1705. In other embodiments, the polynucleotide comprises a nucleotide sequence capable of hybridizing to the nucleotides sequence of SEQ ID NO:1 under highly stringent conditions.
The invention also provides isolated polynucleotides comprising a nucleotide sequence encoding a peptide or protein comprising an amino acid sequence selected from the group consisting of:
(a) the amino acid sequence of SEQ ID NO:2;
(b) the amino acid sequence of SEQ ID NO:2 from amino acids 24 to 422;
(c) the amino acid sequence of SEQ ID NO:2 from amino acids 24 to 365;
(d) the amino acid sequence of SEQ ID NO:2 from amino acids 391 to 422;
(e) the amino acid sequence of SEQ ID NO:2 from amino acids 112 to 422;
(f) the amino acid sequence of SEQ ID NO: 2 from amino acids 112 to 365; and
(g) fragments of (a)-(f) having a biological activity of the human IL-11 receptor.
Host cells, preferably mammalian cells, transformed with the polynucleotides are also provided.
In other embodiments, the invention provides a process for producing a human IL-11R protein. The process comprises:
(a) growing a culture of the host cell of the present invention in a suitable culture medium; and
(b) purifying the human IL-11R protein from the culture. Proteins produced according to these methods are also provided.
The present invention also provides for an isolated human IL-11R protein comprising an amino acid sequence selected from the group consisting of:
(a) the amino acid sequence of SEQ ID NO:2;
(b) the amino acid sequence of SEQ ID NO:2 from amino acids 24 to 422;
(c) the amino acid sequence of SEQ ID NO:2 from amino acids 24 to 365;
(d) the amino acid sequence of SEQ ID NO:2 from amino acids 391 to 422;
(e) the amino acid sequence of SEQ ID NO:2 from amino acids 112 to 422;
(f) the amino acid sequence of SEQ ID NO:2 from amino acids 112 to 365;
(g) the amino acid sequence of SEQ ID NO:2 from amino acids 24 to 359;
(h) the amino acid sequence of SEQ ID NO:2 from amino acids 24 to 345;
(i) the amino acid sequence of SEQ ID NO:2 from amino acids 24 to 324; and
(j) fragments of (a)-(i) having a biological activity of the human IL-11 receptor. Preferably the protein comprises the amino acid sequence of SEQ ID NO:2; the sequence from amino acid 24 to 422 of SEQ ID NO:2; the sequence from amino acid 24 to 365 of SEQ ID NO:2; or the sequence from amino acid 391 to 422 of SEQ ID NO:2. In other preferred embodiments the protein comprises an amino acid sequence beginning with amino acid 23 or amino acid 26 of SEQ ID NO:2. Pharmaceutical compositions comprising a protein of the present invention and a pharmaceutically acceptable carrier are also provided.
The present invention further provides for compositions comprising an antibody which specifically reacts with a protein of the present invention.
Methods of identifying an inhibitor of IL-11 binding to the human IL-11 receptor are also provided. These methods comprise:
(a) combining a human IL-11R protein or a fragment thereof with IL-11 or a fragment thereof, said combination forming a first binding mixture;
(b) measuring the amount of binding between the protein and the IL-11 or fragment in the first binding mixture;
(c) combining a compound with the protein and the IL-11 or fragment to form a second binding mixture;
(d) measuring the amount of binding in the second binding mixture; and
(e) comparing the amount of binding in the first binding mixture with the amount of binding in the second binding mixture;
wherein the compound is capable of inhibiting IL-11 binding to the human IL-11 receptor when a decrease in the amount of binding of the second binding mixture occurs. Optionally, the first and/or second binding mixture may further comprise gp130 or a fragment thereof capable of binding to the protein of claim 11 or the IL-11 or fragment used therein. Inhibitors of IL-11R identified by these methods and pharmaceutical compositions containing them are also provided.
Methods of inhibiting binding of IL-11 to the human IL-11 receptor in a mammalian subject are also disclosed which comprise administering a therapeutically effective amount of a composition containing a human IL-11R protein, an IL-11R inhibitor or an antibody to a human IL-11R protein. Methods of treating or preventing loss of bone mass in a mammalian subject using these compositions are also provided.
In yet other embodiments the invention provides for an isolated polynucleotide comprising a nucleotide sequence encoding a peptide or protein comprising an amino acid sequence selected from the group consisting of:
(a) the amino acid sequence of SEQ ID NO:2;
(b) the amino acid sequence of SEQ ID NO:2 from amino acids 24 to 422;
(c) the amino acid sequence of SEQ ID NO:2 from amino acids 24 to 365;
(d) the amino acid sequence of SEQ ID NO:2 from amino acids 391 to 422;
(e) the amino acid sequence of SEQ ID NO:2 from amino acids 112 to 422;
(f) the amino acid sequence of SEQ ID NO:2 from amino acids 112 to 365;
(g) the amino acid sequence of SEQ ID NO:2 from amino acids 24 to 359;
(h) the amino acid sequence of SEQ ID NO:2 from amino acids 24 to 345;
(i) the amino acid sequence of SEQ ID NO:2 from amino acids 24 to 324; and
(j) fragments of (a)-(i) having a biological activity of the human IL-11 receptor.